Method and apparatus for measuring film thickness and film thickness growth

Abstract

A device for measuring thickness and/or rate of thickness increase of a film comprises at least one piezoelectric element, and first and second electrodes in contact with the piezoelectric element. A method of measuring thickness and/or rate of thickness increase of a film comprises applying a voltage across a piezoelectric element from a first electrode to a second electrode, thereby causing the piezoelectric element to vibrate, and measuring the rate of vibration of the piezoelectric element. Heat may be applied to the piezoelectric element. The piezoelectric element may be formed of quartz crystal, e.g., IT-cut.

1 . A device for measuring the thickness of a film made of a deposit material and/or the rate of increase of the thickness of a film, made of a deposit material, comprising: 
 at least one piezoelectric element having a first region in contact with one electrode and a second region in contact with another electrode;    at least one source of a deposit material, each said piezoelectric element being exposed to said source; and    a heater which heats at least one said piezoelectric element.    
     
     
         2 . A device as recited in  claim 1 , wherein said heater heats said at least one piezoelectric element to a temperature of at least about 50 degrees C.  
     
     
         3 . A device as recited in  claim 1 , wherein said at least one piezoelectric element comprises quartz crystal.  
     
     
         4 . A device as recited in  claim 3 , wherein said at least one piezoelectric element is selected from an AT-cut, an IT-cut and an SC-cut quartz crystal.  
     
     
         5 . A device as recited in  claim 4 , wherein said at least one piezoelectric element is an IT-cut quartz crystal.  
     
     
         6 . A device as recited in  claim 1 , further comprising a power supply which applies a voltage across each said piezoelectric element.  
     
     
         7 . A device as recited in  claim 1 , wherein said heater is in contact with a body, said at least one piezoelectric element being in contact with said body.  
     
     
         8 - 12 . (cancelled)  
     
     
         13 . A method of measuring the thickness of a film made of a deposit material and/or the rate of increase of the thickness of a film made of a deposit material, comprising: 
 applying a voltage across rat least one piezoelectric element thereby causing each said piezoelectric element to undergo vibration    exposing each said piezoelectric element to a source of a deposit material;    applying heat to at least one said piezoelectric element; and    measuring a rate of vibration for each said piezoelectric element.    
     
     
         14 . A method as recited in  claim 13 , wherein said at least one piezoelectric element is maintained at a substantially constant temperature.  
     
     
         15 . A method as recited in  claim 14 , wherein said at east one piezoelectric element is maintained at a temperature of at least about 50 degrees C.  
     
     
         16 . A method as recited in  claim 13 , wherein said at least one piezoelectric element comprises quartz crystal.  
     
     
         17 . A method as recited in  claim 16 , wherein said at least one piezoelectric element is selected from an AT-cut, an IT-cut and an SC-cut quartz crystal.  
     
     
         18 . A method as recited in  claim 17 , wherein said at least one piezoelectric element is an IT-cut quartz crystal.  
     
     
         19 . A method as recited in  claim 13 , wherein said applying heat to said at least one piezoelectric element is carried out by contact heating a body, said piezoelectric element being heated thereby through direct or indirect contact with said body.  
     
     
         20 - 24 . (cancelled)  
     
     
         25 . A method of depositing a film and measuring the thickness of the film and/or the rate of increase of the thickness of the film, comprising: 
 applying voltage across at least one piezoelectric element thereby causing each said piezoelectric element to vibrate    depositing a deposit material onto each said piezoelectric element;    applying heat to at least one said piezoelectric element; and    measuring a rate of said vibration of said piezoelectric element.    
     
     
         26 . A method as recited in  claim 25 , wherein said at least one piezoelectric element is maintained at a substantially constant temperature.  
     
     
         27 . A method as recited in  claim 26 , wherein said at least one piezoelectric element is maintained at a temperature of at least about 50 degrees C.  
     
     
         28 . A method as recited in  claim 25 , wherein said at least one piezoelectric element comprises quartz crystal.  
     
     
         29 . A method as recited in  claim 28 , wherein said at least one piezoelectric element is selected from an AT-cut, an IT-cut and an SC-cut quartz crystal.  
     
     
         30 . A method as recited in  claim 29 , wherein said at least one piezoelectric element is an IT-cut quartz crystal.  
     
     
         31 . A method as recited in  claim 25 , wherein said applying heat to said at least one piezoelectric element is carried out by contact heating a body, said piezoelectric element being heated thereby through direct or indirect contact with said body.  
     
     
         32 - 36 . (cancelled)